Manhole cover lifting apparatus



Jan. 9, 1968 F. P. DAVENPORT MANHOLE COVER LIFTING APPARATUS Filed May16, 1966 FIG.

FIG. 2.

FIG. 7.

INVENTOR.

T R 0 P N W. A D P K N A R Y B United States Patent 3,362,684 MANHOLECOVER LIFTING APPARATUS Frank P. Davenport, 659 Church Lane, Yeadon, Pa.19050 Filed May 16, 1066, Ser. No. 550,322 6 Claims. (Cl. 254-131)ABSTRACT OF THE DISCLOSURE Means for lifting the covers of manholes andthe like comprising a key insertable through an opening in the cover andengageable with the under side thereof and leverage means cooperativewith the key whereby the cover may be dislodged from its seat.

This invention has to do with a specialized implement useful primarilyin dislodging, removing and replacing the, usually cast iron, covers ofmanholes of the type employed for affording access to subterraneanconduits, pipes, mains and the like and with a combination apparatusincluding such implement and a forked lever operating bar adapted forengaging the implement after the latter has been releasably secured to amanhole cover whereby the latter may be dislodged from its seat andindependently moved about at will.

Manhole covers are often left undisturbed for long periods on themetallic seats or rims of manhole structures and through the corrodingaction of natural elements or the pressure of traific passing over themor a combination of both, sometimes become so firmly attached to theirseats they can be dislodged only with considerable difficulty. Moreover,even when dislodged the covers are relatively heavy and cumbersome toban dle yet as far as I am aware no convenient tool or combination oftools has thus far been provided to facilitate either of theseoperations, which because of field conditions must necessarily often bemanual as distinguished from power tool ones.

It is therefore a principal object of the invention to provide animplement hereinafter generally designated a key designed forassociation with a manhole cover of any of a number of specific types tofacilitate removal of the cover from its seat to afford access to theinterior of the manhole, its movement to an out of the way location andfinally replacement on its seat after the manhole has been serviced.

A further object is to provide a key of the above character adapted forassociation and combination with a forked operating bar of novelconstruction with the aid of which the key, whether disposed parallel ornormal to a diameter of the cover, is conveniently manipulated first todislodge the cover from its seat, then to translate it to an out of theway point while the manhole is being serviced and finally to return itto its seat.

Another object is to facilitate the handling of manhole covers by theprovision of specially designed apparatus having novel characteristicswhich render it eminently suitable for this purpose.

Other objects, purposes and advantages of the invention will hereinaftermore fully appear or will be understood from the following descriptionof a preferred embodiment of itillustrated in operative relation to amanhole and its cover in the accompanying drawing in which:

FIG. 1 is a side elevation of said embodiment in which a typical manholecover is fragmentarily represented in section;

FIG. 2 is an end elevation thereof;

FIG. 3 is a perspective view of the apparatus in operative relation to amanhole cover of a usual type and including a specially designedoperating bar fragmentarily represented in association and combinationtherewith;

FIG. 4 is a similar view of the apparatus but in relation with a coverof another specific type;

FIG. 5 is a fragmentary top plan view of the operating bar to whichreference has just been made;

FIG. 6 is a fragmentary side elevation thereof, and

FIG. 7 is a fragmentary front view of the bar.

Referring now more particularly to the construction and operation of theapparatus as shown in the drawing it will be understood that themanholes to which reference has been made are generally permanentsubterranean structures having as access ports circular verticallydirected openings defined by rigid metallic rims into which the coversare seated to form closures for the manhole. These covers are normallymade of cast iron or steel, but sometimes are composite disks includingferrous metal forms with fillings of Portland cement or the like. Inmost instances, however, whatever he the specific structure of themanhole cover, which of course constitutes no part of the presentinvention, openings through the cover are provided to enable a tool tobe inserted therethrough for lifting the cover from its seat in themanhole rim when access to the manhole is desired.

These openings are often rectilinear slots respectively located near theperipheral edge of the cover, a pair of slots usually being provided,and while sometimes the slots have their longer axis coincident with adiameter of the cover in other instances they are disposed at rightangles to such diameter while certain manufacturers prefer to provideintersecting slots of both descriptions producing in effect apertures inthe form of small open crosses in the covers. It is here immaterial,however, which of these several different forms of openings beencountered in a specific instance as the apparatus illustrated and nowto be more fully described is adapted for utilization interchangeablywith any of them.

Said apparatus comprises a key generally designated 1 having a body 2made from heavy ferrous metal, preferably one-half inch steel plate orthe like, in which transverse bores are formed as will hereinafter morefully appear. Considering the key as fronting toward the left when inthe position shown in FIG. '1, from body 2 depends a leg 3 having at itslower extremity a foot 4 terminating in a toe 5, the upper surface 6 ofwhich preferably is fiat or substantially so and normal to the frontedge of the legs, these parts being of such dimensions they can beentered in the slot S in a manhole cover C with the toe extending towardthe manhole rim R and beneath and in contact or approximate contact withthe underface of the cover substantially as shown in said figure. Abovethe upper extremity of the front edge of the leg the periphery of thebody extends forwardly, upwardly and thence rearwardly preferably in asmooth curve and is finally carried for wardly to meet the rear face ofthe leg, thus forming a shoulder 7 substantially parallel to the upperface 6 of the toe and in a plane spaced above the latter a distancesufficient when the leg is in the slot to overlie the cover adjacent theproximate end of the slot, desirably with a slight clearance between thecover and the key.

To maintain the key in a position substantially normal to the cover whenthe key leg is extended through the slot suitable means are providedpreferably comprising a stub shaft 10 extending through a bore 11 in thebody and carrying eccentrically bored sleeves or cams 12, 13 adapted torest on the cover on each side of the key, the cover normally having acorrugated or other ornamentalized pattern (not shown) on its upperface; thus by rotation of the sleeves they can be brought intoengagement with the upper surface of the cover whatever be itsconfiguration for the justrnentioned purpose. Of course the sleeves aresuitably held on the stub shaft in any convenient way as by pins 14, 15extending transversely through the shaft beyond the extremities of thesleeves.

The key further embodies means adapted for cooperation with an operatingbar of suitable conformation, said means being selectively employableeither when the key is disposed with its body coincident with a diameterof the cover or at right angles thereto as when the slots therein arenormal to such diameter. More particularly therefore a stub shaft 16 isextended through a bore 17 in the body of the key and firmly fixedtherein as by a press fit and/ or by welding to the body and, on eachside of and a little below this shaft, the body may be provided withbores 18, 19 adapted for reception of the tines of a forked operatingbar as hereinafter more fully explained.

When it is desired to raise through the medium of my invention a manholecover C having a slot S the-rethrough, the leg of the key is projectedthrough the slot and manipulated so that its toe and shoulder 7 engageor at least are approximately parallel respectively to the lower andupper faces of the cover and to maintain the key upright cams 12, 13 arethen manually rotated if necessary into contact with the upper surfaceof the cover; the key thereafter remains substantially generally normalto the cover surface.

After the key has been thus releasably associated with the cover Clifting means may be applied to the key first to dislodge the cover fromits seat in the rim R of the manhole M, then to move it to a positionapart where it cannot interfere with manhole servicing operations andfinally to return the cover to its original position. For this purpose Iprefer to employ a special tool or bar generally designated 20, having asole plate 21 from one end of which project spaced parallel tines 22, 23between which the plate is dished to provide a hollow trough 24 and,from adjacent the heel portion 25 of the plate, desirably carrying adownwardly projecting boss 25' to serve as a fulcrum, a handle 26 weldedto the plate projecting rearwardly and upwardly at an angle of about 40to the plane thereof. Tines 22, 23 are spaced to embrace key 1 edge-Wise and to engage beneath stub shaft 16 or, when employed inassociation with a cover C having slots S normal to the cover diameteron which they lie, to enter and extend through bores 18, 19 in the key,the end of shaft 16 adjacent the plate then resting in trough 24. Ineither instance boss 25' of the sole plate can initially fulcrum on rimR of the manhole or any other suitable support whereby manipulation ofthe bar enables the cover to be dislodged to free it from wedged orfrozen adherence to its seat, thereafter to be moved to a remote placeand finally returned to its original seat over the manhole, the cover,key and bar remaining in interlocked relation through these severaloperations.

While it is usually most convenient to dispose the key in respect to themanhole cover to be removed in such relation that tool 213 can engageunder stub shaft 16, or have its tines entered in holes 18, 19 with theheel of the tool or its boss seating on the manhole rim R, it will beapparent that in certain instances some other bar supporting means maybe preferred while first dislodging the cover from the rim; in othersthat it may be unnecessary to utilize a leverage action for firstdislodging the cover which may therefore be raised more or less directlyfrom the manhole and moved away by a simple lifting effort on the partof the operator.

Moreover while I have herein disclosed a manhole cover lifting key ofspecific character as illustrated in the drawing and have described itas operatively associated and combined with a bar also more or lessspecifically described and illustrated, it will be understood the saidkey does not always require for its useful employment utilization ofsaid bar, as other means may in many instances be advantageouslyemployed for lifting it and a cover to which it may be attached; furtherthat numerous changes and modifications in the form, construction,arrangement and relationship of the parts and components of my apparatuswill readily occur to those skilled in the art and may be utilized ifdesired without departing from the spirit and scope of the invention asdefined in the appended claims.

Having thus described my invention, I claim and desire to protect byLetters Patent of the United States:

1. An implement for association with a manhole cover having a slotextending therethrough, said implement comprising a body and a legterminating in a foot having a toe adapted to engage beneath the coverwhen the leg is projected through the slot, a shoulder on the bodyoppositely directed from the toe with respect to the leg disposed tooverlie the cover when the leg is so projected, means extendingtransversely of the body for engagement by an operating bar when theimplement is so associated with the cover, and means for maintaining theimplement sub stantially upright when so associated comprising a shaftextending oppositely from the body and eccentrically bored sleevesrotatable thereon.

2. An implement as defined in claim 1 in which the means for engagementby the bar define spaced bores extending through the body for receptionof tines on the extremity of an operating bar.

3. The combination of an implement for association with a manhole coverhaving a slot extending therethrough, said implement comprising a bodyand a leg integral therewith terminating in a foot having a toe adaptedto engage beneath the cover when the leg is projected through the slot,a shoulder on the body oppositely directed from the toe with respect tothe leg disposed to overlie the cover when the leg is so projected, andmeans extending transversely of the body receiving an operating bar whenthe implement is so associated with the cover, said bar including a soleplate having parallel spaced projecting tines engaging said means, aheel portion adapted to seat on the rim of the manhole on which thecover is disposed and a handle projecting angularly rearwardly andupwardly from the heel portion with respect to said tines formanipulation by an operator to tilt the cover relatively to said rim bya pivotal movement of the bar about the region of engagement of saidheel portion with said manhole rim.

4. The combination defined in claim 3 in which the operating barreceiving means comprise a stub shaft projecting outwardly from oppositesides of the body.

5. The combination defined in claim 3 in which the operating barreceiving means define the interior surface of a bore extending throughthe body.

6. The combination defined in claim 3 in which the operating barreceiving means define spaced bores extending through the body forreception of said tines.

References Cited UNITED STATES PATENTS 441,113 11/1890 Sastmann 254131 X1,517,591 12/1924 Shook 254-131 2,375,409 5/1945 Glitsch 254 X 2,961,75611/1960 Johnson 29-235 OTHELL M. SIMPSON, Primary Examiner.

